This invention relates to a catalytic process for paraffin isomerization producing branched paraffin isomers under strong acid catalyzed conditions and in the presence of adamantane hydrocarbons as hydride transfer catalysts.
Isobutane-olefin alkylation or paraffin isomerization under strong acid conditions are well-known processes for producing a wide variety of useful hydrocarbon materials and particularly, gasoline additives. For example, trimethylpentanes, which can be produced by alkylating isobutylene with isobutane in sulfuric acid or liquid HF, are commonly used for blending for gasoline octane improvement. An example of an acid catalyzed reaction process is described in U.S. Pat. No. 3,231,633.
Hydrocarbon conversion processes employing novel Lewis acid systems are disclosed in U.S. Pat. Nos. 4,229,611 and 4,162,233, both assigned to Exxon Research and Engineering Company.
U.S. Pat. No. 3,671,598 describes a process for isomerizing saturated cyclic hydrocarbons under strong acid conditions in the presence of an adamantane hydrocarbon. However, no suggestion is made that a similar system might be useful for isomerizing paraffinic hydrocarbons.
New methods for producing such branched paraffinic hydrocarbons are constantly being searched for in an effort to increase selectivity yield, and reaction rate, and decrease the cost of said process.